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Good vibrations indeed. Female red mason bees (Osmia bicornis, seen in video) choose to have sex with a male based on how well he can vibrate his thorax. Initially scientists thought that the females were cuing in on how long the males could keep the vibration going—a testament to fitness and stamina. But along the way, researchers discovered that females from a subspecies native to the United Kingdom preferred U.K. males over German members from the opposite subspecies regardless of who could vibrate the longest. This led scientists to wonder whether information about the bees’ geographic origin and subspecies identity was also conveyed through the vibrations. To be sure, they needed away to control for confounding variables, especially odor. Today in Current Biologyscientists report the development of a novel test that uses a vibrating magnet attached to the bees’ thorax to impose one male’s vibrational pattern onto another male’s body. Before the magnet treatment the least compatible bee pairings were U.K. females and German males. But after scientists recorded the vibrations of U.K. males and duplicated them in the magnet strapped to the Germans, the U.K. females became much more receptive. Like Cyrano de Bergerac feeding Christian lines from underneath Roxane’s balcony, the German males had much better luck when they mimicked the premating communication of another. The scientists point out that, in the wild (where there are no magnetic wingmen), the females’ preference for local males’ vibrations could be an early sign of speciation in the red mason bees: If the females of one subspecies stop mating with the other subspecies entirely, the two lineages may eventually become incompatible and diverge into two separate species.

This image shows the functional connections in the brain that tend to be most discriminating of individuals. (Credit: Emily Finn)

Each person is unique. You can identify people by their DNA, fingerprints, personal preferences and behavior. But new research out of Yale University has shown we have another unique identifier: How our brains work.

“We all have this intuition that people are unique. We all have our own strengths and weaknesses, our quirks and personalities, what we’re good at and how we handle things,” says study co-first author Emily Finn, a pHD student in neuroscience at Yale. “It’s very easy to observe that from the outside … but it’s been pretty hard to find correlates in brain activities.”

And yet, it is the brain that makes all those differences possible. Knowing this, Finn and co-first author Xilin Shen, an associate research scientist at Yale, used functional magnetic resonance imaging (fMRI) scans to see if our brains each have a unique “fingerprint” that could distinguish one person from another.

Brain ID

To get a glimpse at the way specific parts of the brain function in real time, scientists use fMRIs to repeatedly scan a person’s brain while they complete a specific task. The noninvasive technique measures the amount of blood flowing to certain parts of the brain — more blood indicates more activity. Most fMRI studies average brain function over a study population, which has let scientists learn what parts of the brain work under certain circumstances. The convention among scientists, Finn said, was that it is hard to get meaningful information out of a single person’s fMRI scan.

Finn and Shen wanted to challenge conventional thinking.

They scanned the brains of 126 participants in the Human Connectome Project while they performed several different tasks. They mapped the connections in the prefrontal cortex and parietal lobes — recently evolved parts of the brain involved in complex functions like attention and language — to develop connectivity profiles of each person. They found that each person’s bran activity profile was indeed unique.

“The same brain doing two different things always looks more similar than two different brains doing the same thing,” says Finn. “It’s something that maybe seems intuitive outside the field but it’s something no one had been able to show.”

Predicting Performance

Beyond proving each person’s connection profile was unique and distinguishable from another person’s, Finn and Shen also looked to see if it was possible to use profile data to accurately predict someone’s performance on a test. To measure performance, they first developed a predictive model; they then — 126 times — removed one subject’s profile and put the remaining 125 through their model to see if it could accurately predict the person’s performance on a test that measured reasoning and the ability to see patterns.

Because they had the subjects’ actual test results, they could see how well the model stacked up, and found it was able to predict performance in a statistically significant way.

A Bigger Role for fMRI

Finn says the predictive portion of the study was “more a proof of principle” that brain profiles could be linked to cognitive behavior.

“If we can predict that,” says Finn, “maybe we can predict something we can’t just give a test for, like the risk for mental illness or who would respond best to some kind of drug.”

That’s what led her and others on the team to do this work, she said.

“You as a scientist like to think the things you’re discovering about the brain will help people someday,” says Finn.

She wanted to see if there was a way to make fMRI scans useful from a clinical standpoint, where doctors could someday tell from the scan whether a person might be at higher risk for developing a mental illness, and to then implement a support plan that could improve their outcome. Currently, fMRI scans are really only used in research settings, Finn said, because it is harder to get usable information out of the scans. Instead, structural MRIs, which take static photos of the brain, are used regularly to diagnose problems in the brain, like tumors or strokes.

“I think doing this type of work and pushing the boundaries of what we can get out of one person’s scan is the first step down the road to make this brain scanning technology have real-world applicability,” says Finn.

Phosphorus was first discovered by people looking for riches in urine, explains a video by the American Chemical Society’s Reactions series. Seventeenth century alchemists thought urine, with its golden color, might help them turn other substances into gold. When they boiled off the liquid, they got a white glow-in-the-dark substance: phosphorus. The element is a key component of organic molecules and of modern products such as matches and fertilizers.

A tropical depression that formed Sunday in the Atlantic has strengthened into a tropical storm that could bring a lot of rain to parts of the U.S. East Coast later this week — possibly on top of a big rainfall event that’s already cranking up for the northern Appalachians and New England over the next several days.

Click on the image above and say hi to Tropical Storm Joaquin.

The forecast for Joaquin is highly uncertain at the moment, thanks to difficulties the weather models are having in dealing with the evolution of other weather disturbances that will likely affect the storm. This is especially true of a trough that’s forecast to develop over the Southeastern United States, according to this morning’s forecast discussion from the National Hurricane Center.

While a large portion of the East Coast is within the forecast cone for tropical storm force winds, the highest probability right now is between 20 and 30 percent, as this graphic shows:

The probabilities of sustained (1-minute average) surface wind speeds equal to or exceeding 39 miles per hour — tropical storm force— for Tropical Storm Joaquin. This wind speed probability map is based in part on forecasts of the track, intensity, and wind radii from the National Hurricane Center. (Source: NHC)

That could change over the next few days — in either direction. Joaquin could strengthen and make landfall, possibly even as a hurricane, or it could turn out to sea and never hit land.

| Update 9/30/15: Here is the latest from the forecast discussion page of the National Hurricane Center:

Joaquin is expected to become a hurricane within 24 hours, with additional intensification likely thereafter.

But Joaquin’s future track is still very highly uncertain. Some model runs take it completely out to sea. Others show the storm making landfall on the East Coast. The NHC’s current official forecast “lies between these possibilities.”

I think at this point we should take it all with a grain of salt. |

Whatever turn Joaquin takes, the U.S Eastern Seaboard already is in for heavy precipitation — independent of the storm. And Joaquin could later add insult to injury.

A remarkable paper just published in PLoS ONE reports on what is, I think, one of the largest psychological experiments of all time.

Researchers Elizabeth L. Paluck and colleagues partnered with a TV network to insert certain themes (or messages) into popular dramas shown on US TV. They then looked to see whether these themes had an effect on real world behavior, ranging from Google searches to drink-driving arrests.

The study was based on three prime time Spanish-language dramas (telenovelas) which have a viewership of around 1.2 million people per week. Telenovelas are a genre similar to English-language soap operas except shorter, most lasting about a year. Into these shows, eight messages were added, ranging from health and safety (benefits of low cholesterol, dangers of drink driving) to community building (register to vote, scholarships for Hispanic students.)

In total, there were 23 scenes, featuring 16 minutes and 51 seconds of footage. The scenes were “not central to the shows’ plots” but “many involved the shows’ main characters.” What makes this a genuine experiment (rather than just an observational study) is that the researchers used randomization to determine when in the season to broadcast each message.

So did it work? Not really. The airing of scenes featuring the Hispanic Scholarship Fund did lead to large (but temporary) spikes in the number of people visiting that organization’s website.

However, there was no evidence that messages about voter registration led to increases in the number of Hispanics actually registering:

Nor did Google searches for terms related to the messages increase following each broadcast:

The authors conclude that

In our study, the airtime devoted to the suite of messages would have been worth millions of dollars, but the cumulative effect of these messages on the general population was small and short-lived.

The use of telenovelas to spread health and social messages has a long history. In fact, according to Wikipedia, the genre has “decreased credibility”among viewers today because of heavy-handed government messaging in the past. I wonder if this could be part of the reason for the weak effects? Perhaps this paper will affect the credibility of telenovelas still further?

One thing Paluck et al. don’t discuss is the ethics of this project. They obtained Institutional Review Board (IRB) approval. However, at least on the face of it, there is an ethical issue here. This was an experimental manipulation of human behavior, but the participants did not give informed consent to be part of the research. Now, when Facebook announced that they had done a randomized study on nearly 700,000 unsuspecting users, people weren’t happy. The present study differs from that one in a number of ways but I think some people will be uncomfortable about it.

In a novel surgery, surgeons have transplanted the world’s first 3D printed titanium rib cage, NPR reports. A 54-year-old man who lost his sternum and four rib pieces when doctors removed a cancerous tumor was the recipient of the metallic implant, the surgeons describe in the European Journal of Cardio-Thoracic Surgery. Engineers with the Australian company Anatomics used CT scans of the man’s chest to custom design the device before printing it at a government lab. The 3D printing technology is particularly useful in these extreme cases that call for extensive reconstructions, helping craft an implant that “fitted like a glove,” the surgeons say. Such accuracy of fit may help to reduce any potential complications with the transplant.

Summary: The first true three-dimensional picture of submarine canyon habitats has been produced using a unique combination of marine robotics and ship-based measurements. The information captured in this new set of maps ranges in scale from the 200km canyon down to the size of an individual cold-water coral polyp, and will be used to inform the management of the only English Marine Conservation Zone in deep water.

An orange Roughy in a coral reef was taken by the Isis ROV.

Credit: The National Oceanography Centre as part of the CODEMAP project

The first true three-dimensional picture of submarine canyon habitats has been produced using a unique combination of marine robotics and ship-based measurements. The information captured in this new set of maps ranges in scale from the 200km canyon down to the size of an individual cold-water coral polyp, and will be used to inform the management of the only English Marine Conservation Zone in deep water.